Why does your 1994 ford crown Victoria rear end shift down or it could be the transmission slipping into another gear while driving along at a normal speed?

Answer 1

it would be your trans the rear end doesnt shift check last time your trans was serviced and check your modulater valve Also check the torque converter lock up. Torque converter lock up occurs during normal driving in the mph range of 45-55 mph. This is another shift(an over drive if you will) you feel it shift in and then out when accelerating or slightly tapping the foot brake. take the vehicle on a long straight away and drive it easy ....feel the 1-2 shift....then the 2-3 shift....now with a steady gas pedal feel another light shutter type shift at around 45-55 MPH??? This is the Torque converter lock up.......when you feel it shift in.......keep a steady speed in the range of 45-55 and oh so very lightly just "TAP" the brake pedal enough to put the brake lights on but not enough to make the brakes engage....get it?? When doing this repeatedly the brake light electrically signal the converter to diss engage....get it? You should feel the shutter each time coming out of lock up and then going back into lock up until you tap the brake pedal again. That will rule in or out the theory of it being or not being a normal torque converter lock up shutter.